The group pushing to replace Andrew Jackson with a woman on the $20 bill has revealed its final four candidates after more than 256,000 votes were placed.

The four are former first lady Eleanor Roosevelt, abolitionist Harriet Tubman, civil rights activist Rosa Parks and Wilma Mankiller, the first woman elected chief of a major Native American tribe. Voting for the finalist is now open. The group behind the push, Women On 20s, has not yet set a specific end date for the final vote.

The group's original list of 100 names was winnowed down to 60 through informal discussion, then to 30 via a two-part survey and to 15 by a group of outsiders that included women's history experts. The public was then able to choose their three favorites from the list of 15 candidates, which also included feminist Betty Friedan, birth control activist Margaret Sanger, women's suffrage leader Susan B. Anthony and conservationist Rachel Carson.

Women On 20s revealed that the top three vote recipients — Roosevelt, Tubman and Parks — received more than 100,000 votes each. It also said on its Web site that Mankiller, who made the list of 30 but not the list of 15 that the public voted on, was selected for the final ballot "by popular demand" and "strong public sentiment that people should have the choice of a Native American to replace Andrew Jackson."

The group is targeting the $20 bill not only because the year 2020 will be the centennial of the 19th Amendment, which granted voting rights to women, but because Jackson helped pass the Indian Removal Act of 1830, which forced Native American tribes off their land in a relocation commonly referred to as the Trail of Tears.